The present study aims to assess the quality of implementation of an evidence-based early drug abuse preventive intervention (the Early Risers "Skills for Success" program) transported to 32 geographically dispersed rural schools. Two major goals are (a) to examine the capacity of community service providers to maintain fidelity with the intervention model, and (b) to investigate service system factors that facilitate or impede fidelity as well as factors that are associated with successful adaptations. Children will be screened for aggressive/disruptive behavior during the 1st and 2nd grades and followed through the 4th and 5th grades. The prevention trial will include an intensive two-year intervention phase followed by a one-year booster phase. Three dimensions of fidelity (adherence, exposure, and quality of delivery) will be measured over multiple observations for each of five intervention components across multiple program implementers. Statistical analyses will determine whether variation in program fidelity is related to variation in changes in child, parent, and family outcomes, controlling for the effects of client participation. A multilevel path analysis model will examine hypothesized paths between selected organization and service system level variables (organizational climate, supervisory practices, and practitioner characteristics) and dimensions of fidelity. Last, the study will conduct a cost-effect analysis.